The Yankees Are Coming

Look, this is a Viking longship: The bottom of the boat uses a whole piece of large oak as the keel to absorb the impact from head to tail. The ship's plates are layered like scales and fixed by rivets, making them strong and durable. The bow and stern of the boat are exactly the same, allowing you to turn around and escape at any time. A big sail and two rows of long oars, let it run, How about it? Is it simple and practical? Ingvar: You mean, I'm going to sail the entire North Sea in this thing? Short version: A useless college student and a veteran Crusader King player traveled to ninth-century Norway to become a Viking pirate, leading a precarious life of robbery. However, what does it mean to be brave and not afraid of pain? What do you mean my illness will be cured by drinking this potion? [Micro fictional history + some extraordinary elements + golden finger? PS: Fandom, lighthearted and funny, but mainly about customs